The present invention relates to endoscopic biopsy forceps that is passed through the forceps channel in an endoscope to collect a tissue specimen for biopsy from within a body cavity.
Endoscopic biopsy forceps generally comprise a sheath to be inserted into or removed from the forceps channel in an endoscope, a manipulating wire extending through the sheath, and a pair of forceps cups provided at the distal end of the sheath that are driven to open and close by advancing and retracting the manipulating wire along the longitudinal axis.
To collect a tissue specimen, the forceps cups are closed but they might slip on the mucosal surface and fail to attain the intended result. To avoid this problem, some endoscopic biopsy forceps are provided with a needle that extends forward to project into the central part of a pair of forceps cups.
To collect a tissue specimen for biopsy with this type of endoscopic forceps, a pair of forceps cups are opened and the needle is pierced through the mucous membrane in the diseased part so as to fix the forceps cups in position; then, the manipulating wire is pulled toward the operator to close the forceps cups, whereupon a tissue specimen is collected within the pair of forceps cups.
A problem with this approach is that the needle pierced into the central part of the specimen can damage and deform the tissue of this vital part of the specimen to such an extent that the operator is unable to determine correctly if the diseased part is malignant or not.
An object, therefore, of the invention is to provide endoscopic biopsy forceps that allows a non-deformed, high-quality tissue specimen to be readily collected from the correct target position.
According to the invention, a needle or needles are provided that extend forward to project into and/or along a pair of forceps cups and this allows the tip portion of biopsy forceps to be positively secured on the mucosal membrane so that a tissue specimen of the diseased part can be easily detached from the correct target position and collected into the forceps cups. What is more, the needle or needles are offset from the center of the pair of forceps cups and this enables collection of a non-deformed, high-quality tissue specimen.
Endoscopic biopsy forceps preferably comprises a sheath, a manipulating wire extending through the sheath, a pair of forceps cups provided at the distal end of said sheath which are driven to open and close like beaks by advancing and retracting the manipulating wire along the longitudinal axis, and a needle that extends forward to project into and/or along said one pair of forceps cups, the needle being offset from the center of said one pair of forceps cups.
If desired, a plurality of needles may be positioned side by side and offset from the center of said one pair of forceps cups.
The present disclosure relates to the subject matter contained in Japanese patent application No. Hei. 11-106570 (filed on Apr. 14, 1999), which is expressly incorporated herein by reference in its entirety.